Selective apparatus for systems of communication.



E. CLEMENT. SELECTIVE APPARATUS FRsYsT Ms OF COMMUNICATION. APPLICATION FILED 00111, 1906. 1,107,149, Patented Aug. 11,- 1914 2 SHEETSSHEET 1.

Svwentoz E. E. CLEMENT. v SELEGTIVE APPARATUS 20 SYSTEMS OF COMMUNICATION.

APPLIUATION FILED 0OT.11, 1906 Patented Au .-11,"191 4.

I 2 SHEETS SHEET 2.

animator Witness W UNITED STATES PATENT OFFICE.

EDWARD E. CLEMENT, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR, BY MESNE ASSIGNMENTS, TO FREDERICK C. STEVENS, 01E ATTICA, NEW YORK.

SELECTIVE APPARATUS FOR SYSTEMS OF COMMUNICATION,

Specification of Letters Patent. P t t Aum 11 9 Application filed October 11, 1906.

Serial No. 338,465.

To all whom it may concern:

Be it known that I, EDWARD E. CLEMEN'I,

a citizen of the United States, residing at lVashington, in the District ofUolumbra,

have invented certain new and useful. Improvements in Selective Apparatus for Systems of Communication, of which the fol lowing is a specification, reference being had. therein to the accompanying drawing.

My inventimi relates to systems of com.- munication, and has for its object the production of a simple and efficient means of selecting any one of a suitable number of pieces of apparatus or circuits to lee-affected in due course.

Briefly stated, my invention consists in making a combination of relays which control the apparatus or circuits in question, the number oi relays being less than the total number of circuits or pieces of apparatus to be controlled. The. relays are selected in proper combinations to pick out certain C11- cuits by switches operated by circuit closers. In. the present case these circuit closers are illustrated and described. as simple keys or pushbuttons and the switches comprise step ping magnets, separate series oi contacts over which the wiper on each switch passes together with release mechanism for returning the switch parts to normal. For the purpose of illustration I have shown one telephone circuit which may be connected to any one of thirty others through the agency of thirteen relays, three of which are group selectingrelays and ten of which are adapted to select any one line in either of the three groups. The group relays are connected to a switch and the line selecting relays are connected to a separate switch. For purposes oi clearness and room I have shown .only three group selecting relays but have shown a ten point switch for controlling. It will he understood that as many group solccting relays as there are points in th. switch may be used. The underlying prir cipl-e or". the inuention is this; that by requiring a circuit to he closed at two points in order to effect its completion, combinations may he made which are. in'ipossible where the circuit is only closed at one point. In

the present case I divide the thirty individual circuits into three groups of ten each which are normally iliscoi'merted from anything. Each group, however, goes to ten pairs of contacts on a relay which closes are connected separately and respectively to' the ten multiple branches of the three group relays.

Assuming that circuit #26 is to be connected to the common circuit, the circuit closer for the group selecting switch is pushed two times thus connecting the second point of the switch and battery to the second relay, the line relay selecting switch is then pusl'ied six times thus putting battery upon the (3th single or unit relay. If battery were at this time on the circuit each one of the relays would be selected as the switch rods were stepped up but I purposely keep battery oil of the line. until after the relays have been selected and then throw battery on the line by a suitable switch. As soon as this is done it will be seen that the circuit is thus closed through #2 branch of the group relay and. through #6 extension of the 6th single relay which is the only one of the group that is closed all the way through. It is obvious that the battery should be disconnected before the release magnet ,is operated.

Fin-theiobjects and ad antages Will be set forth hereinafter and particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawing in which;

Figure l is a diagram showing one embodiruent of my invention; Fig. 2 is a View illustrating a, locking circuit; Fig. 3 is a view showing a modified form of locking circuit.

Referring to Fig. 1, the diagram shows thirty line terminals on one side, any one of which can be selected and connection eilected therewith from the other side. In this diagram I have shown three relays marked re spectively it R and R each of which con trols ten. pairs of contacts. 'Ihese ,I call the tens relays. ()n the other side I have shown ten relays marked R, R, R, R R", it, it, It, It, and R, which I shall call units relays. Each of these relays controls a single pair of contacts. The. reason for showing a pair of contacts is that the circuits controlled by the relays are metallic.

- side of the relays R, R R, etc. The units relays R R R etc., are connected through wires 1, 3, 5, 7, 9, 11, 13, 15, 17 and 19, to the ten contact pens P respectively of the switch S whose contact wiper 8* is .connected through to battery B by the wire 8 and the switch a.

The switches S and S are similar in every respect and in describing them I will refer to the switch S because all of the contact pens are utilized whereas with the switch S only three of the contact pens are used in this instance. A. magnet m grounded upon one side is connected to the battery B through a key K and a wire is. Pivoted in proper relation so as to be magnetized by the core of the magnet m is an armature m normally retracted by a spring at? and carrying upon its outer end a spring pressed pawl m adapted to engage and step up the switch rod 1m which carries the contact wiper s. As the rod m" is stepped up it is engaged by a locking pawl 471 provided with a rearwardly projecting tongue m engaged by the projecting arm m of the armature m This armature m is controlled by the release magnet m. I

The operation of the switch is as follows: Then the key K is depressed, battery current is put upon the magnet m by the following circuit: battery, K wire 01:, magnet m, and ground. The magnet thus energized attracts its armature 'm/ and throws the pawl m into engagement with one of the ten teeth t, on the rod 'm, thus stepping it up so that its wiper 8 contacts with the first pen in the group P. When the key is released the armature m drops back to normal position and is held out of engagement with the teeth by a stud t, the 'rod carrying the wiper s is held in this position by the locking pawl wa until the key K controlling the release magnet is pressed, at this time the fol.-

lowing circuit is closed; battery B, 7:, wire 00, magnet m" and ground. The magnet m being thus energized attracts its armature m and throws the arm into engagement with the rear\\'ardly projecting tongue on, on the locking pawl m. This throws the locking pawl out of engagement with the switch rod m" and allows it to drop by gravity. It will thus be seen that any relay connected through this switch is then doenergized and the circuit control thereby 'broken.

Having described the operation of the switches I will now proceed to descri e the connection between the switches and A wire a", wiper s, the first contact pen in the.

the difierent sets of relays: Between the two sets of relays a cable G passes which is composed of ten pairs of wires which may be designated by the letters a, b, c, d, e, f, g, h, i, j, which are connected and disposed as follows: All of the pairs are multiplied to the ten pairs of contacts on each of the tens relays R, R and It". Thus the first pair a goes to the first pair of coin tacts on each of the relays R, R and R. The second pair b goes to the second pair ot' contacts on each of these relays, and so on. The correspondingor cooperating contacts of the relays are connected to the individual lines or circuits to be selected, bus, in the relay It appear the terminals of lines #1 to #10, in relay t appear the terminals of lines #11 to #20, and in relay it appear the terminals of lines #21 to #30.

Each of the pairs (Z, Z), 0, etc, is connected to a single pair of contacts in one of the units relays R, R it, etc. Thus the pair (.2 appears only in the relay It, and the pair I' appears only in the relay R, etc. .l have shown the contacts of the units relays connected on one side to a common circuit 12; to which is connected a telephone Q. l have shown line #1 which is the first outside line on the relay R, connected to a telephoim and it is to be understood that all the other terminals may be connected to similar lelcphones or any desired apparatus.

The operation of selecting any one of: the lines represented on the tens relays is as follows: Suppose it be desired to connect the telephone 0 with the telephone Q; the line circuit leading to Q is #1 which appears only in the terminals on relay ll. hence the operator presses the key K to step the rod with its wiper .9 up to the first contact pen in the group F, thus energizing the relay it through the following circuit: battery, wire 8 wiper s, the first contact pen in the group I wire 2, relay R and ground. The relay R in pulling up connects all of the lines #1 to #10 on to the pairs of wires :1, z). c, (7, etc, in the cable C. As these pairs are d istrihnlcd among the relays it, it, it, clr.. it follows that we have thus connected the lines it i to #l() to the relays resywciively from P" to ll. and by ei'icrgizing any one of those rclays we may select any one of the individual lines which have thus become connected. the present instance the operator closes the key ii once thus cminecting the. battery to the magnet in by the following circuit: hattcry l wire .Z". key K, wire 0', magnet in and 'rounr;l. 'lh magnet thus energized steps up the nitch rod m and connects the wiper with the first contact pen in the group P thus c nnecting the relay it. The Switch a is now cluficdiliu's putting battery upon the relays ll and it through th following circuit to the relay l? lmilcry ll, switch a,

In I

group P, wire 2, relay R and ground; and to the relay R through the following circuit: battery B, switch 8 wire 8 wiper s, the first contact pen in the group P,,wire 1, relay R and ground. Thus both relays R and R are energized and connect the respective telephones O and Q and as long as the.

switch a is held upon its contact point to close the circuit of the relays this connection will remain established. As soon as the switch is moved to break the circuit the re lays are deenergized and the'circuit disconnected. The operator then restores the switches by pressing the key K which puts current upon the magnets on and m" by the following circuit: battery B, wire is, key K, wire of, magnet m", and ground and on the other side by the same circuit to the point :0 and thence by wire :0, magnet m and ground. Thus through the divided path :0 00 both magnets .m" m" are energized, pulling up their armatures, to hook their arms m on to the detents m thus when the magnets are again deenergized, retracting the locking pawls m and m in the switches S, S respectively and allowing the switch rods m to drop by gravity and disconnect the wipers s, s from the contact pens.

desired to select and connect with line #17; the switch S is stepped up two points so that it is connected with wire #4 through the relay R and ground and the switch S is stepped up seven points 'or until the wiper s is upon the seventh contact pen in the group P. This puts the relay R in readiness to connect with the pair 9. When the switch a is closed both relays R and It are energized and the circuit for line #17 is completed. The release of these magnets and the release of the switches is the same as before described.

It will be understood that the switches, keys and relays shown herein are merely used for the purposes of illustration, the invention not lying in the switches which have been disclosed in a co-pending application Serial No. 296,853, filed January 19, 1906, or in the relays, but in the arrangement of the tens and units relays, and their circuits with the switches for connecting them and all used in the various combinations so as to produce as great a total of possible selections and connections as is possible with the number of relays and switches involved. It should be observed that the relation of these relays is not limited to simply decimal relation. Thus, the number of contacts carried on the relays R, R etc., is limited only by the requirements of good practice and the possibility of obtaining sufficient power in the actuating electromagnets. The number of these relays is not limited nor is the number of relays R", R etc. For example, twent relays R, R etc., could be provided eac of which had its ten pairs of contacts multiplied in any manner similartothose in the figure. An one of two hundred lines could thus be be ected by increasing the contacts on the switches or ten relays R, R, etc., could be provided each with twenty pairs of contacts. It would then be necessary to provide twenty pairs of contacts in the cable C and twenty individual relays R, It, etc., and twenty contacts in each switch.

Numerous other changes and arrangements might be resorted to without departing in any way from the spirit or scope of the invention and all such changes are contemplated by me and are considered to be within the purview of theappended claims.

I have described my controlling relays as single wound, and depending entirely upon the selective circuit closers. By providing each relay with a second winding, amd a pair of controlling contacts therefor on 1tsarmature,'and by running a common battery wire to all of these contacts, each relay may be made to close its own circuit when it is energized, so that it will remain energized as long as the common battery locking wire is intact. To unlock the relay I place a key in this commonbattery wire so that it may be opened at will for restoring purposes. A still simpler arrangement, which is also self-locking, is to connect one of the contacts on the relay armature with the battery wire, and the other with a point on the battery side of the single winding. Thus, a temporary closure of the relay circuit through the controlling device will cause it to pull up and maintain the battery connections on its single winding as long as the locking wire .is intact. Such self-locking relays are well known in the art, .but their application to my type of selecting system I consider involves invention, and I shall therefore claim the combination.

Having thus described my invention what I claim and desire to secure by Letters Pat cut is:

1. An electrical system for selection comprising a plurality of circuits and contact terminals therefor, a number of stationary connective devices less than thenumber of terminals, means having traveling contacts electromagnetically driven step by step for effecting combinations of said connective devices and thereby completing the circuits and means for releasing the aforesaid means.

2. An electriealsystem for selection and interconnection of line circuits comprising a plurality of line circuits and contact terminals therefor, a number of connecting relays less than the number of terminals,

step by step selective means for effecting combinations ofsaid relays and thereby interconnecting the circuits, and means for restoring the aforesaid means to normal.

3. An electrical system for selection and interconnection of line circuits comprising a plurality of line circuits and contact terminals therefor, a number of connecting relays less than the number of terminals and step by step selective switches variably driven for effecting combinations of said relays to thereby interconnect the circuits. 4. An electrical system of selection and interconnection of line circuits comprising a plurality of line circuits and contact terminals therefor, a number of connecting relays less than the number of terminals, step by step selective switches for effecting combinations of said relays, and thereby interconnecting said circuits and means for restoring said switches.

5. An electrical system for selection and interconnection of line circuits comprising .a plurality of line circuits and contact terminals therefor, a number of connecting relays less than the number of terminals, step by step selective switches less than the number .of relays for effecting combinations of said relays and thereby interconnecting the circuits and means for restoring said switches.

6. In an electrical system for selection the combination with a plurality of line circuits and contact terminals therefor, of a number of group selecting relays, a number of unit selecting relays, all of said relays being less in number than the contactterminals, variably driven step by step means for selecting a group relay and means for selecting a unit relay and thereby forming a combination to interconnect the line circuits for communication.

7. In an electrical system for selection the combination with a plurality of circuits and contact terminals therefor, a plurality of group selecting relays, a plurality of unit selecting relays, all of said relays being less in number than the terminals, stcp by step mean'stor selecting any one of the group reselecting any one of the unit with the operated group. relay and thereby effect a circuit, and means to restore said relay selecting means.

v8. In an electrical-system for'selec-tionthe combination with a plurality of circuits and contact terminals therefor, a plurality of group selecting relays, a plurality of unit sela '5 means for lecting relays, all of said relays being less in number than the terminals, step by step means for selecting any one of the group relays, meansforselecting'any one of the unit relays to thereby effect a combination with the operated group relay and effect a circuit, and

selected and means for restoring said relay selecting means.

9. In an electrical system for selection and interconnection of line circuits the combination with a plurality of line circuits and contact terminals therefor, ot a plurality of sets of connecting relays, step by step means for selecting any one of any set to elect combinations between the sets and thereby interconnect desired circuits, with means for re storing said selecting means.

10. In an electrical system for selection thecombination with a plurality of circuits and contact terminals therefor, of a set of relays each having a plurality of contact pairs, a set of relays each 1 aving a contact pair, means for selecting one of the first mentioned relays and step by step means for selecting one of the last mentioned relays which effects a combination between the two to complete a certain circuit together with means for restoring said selective means.

11. In an electrical system for selection the combination with a plurality o1 circuits and contact tcrn'iina'ls thereof, of a set o t rclays each having a plurality of contact pairs, means for selecting arid energizing any one of said relays to complete half of a combination desired, a plurality of relays each having a contact pair, step by step means for selecting and energizing any one of said rc-' lays to complete the combination started by store simultaneously both of said relay selecting means.

12. In a system of selection for electrical systems, the combination of a plurality of circuits divided into g oups, two or more sets of relays controlling said groups and the units in the groups, with a stepby-stcp variably driven selective switch for each set of relays arranged to select a relay of the set, and means to actuate the same, the total number of controlling relays being less than the number of circuits controlled.

13. In an electrical selecting interconnecting system, a plurality of line circuits, controlling rclays for said line circuits, variably driven electromagnetic switching means for initially closing the circuits of said relays in pairs and in varying combinations, means controlled by each relay foranaintaining its own circuit closed so as to be self-locking, and means to open the relay locking circuits.

14:. An electrical system of selection comprising a plurality ofline circuits to be interconnected, and a' plurality of relays and variably driven step by-st'epselectivc switches operated to set the same so asflto interconnect the circuits.

15. In a, telephone exchange system, a plurality of line circuitsto be interconnected, and means for connecting them comprising a double set of relays, one set acting indimeans for imposing current upon the lines vidually to select a group containing any dethe before mentioned relay and means to resired line, and the other set acting individually to select a unit in the group, together with variably driven selective means acting step by step to select the individual relay in each group corresponding to a desired line to be connected.

16. in a telephone exchange system, a plurality of line circuits and means for connecting them comprising the following instrumentalitics: two groups of relays, each relay oi. one group containing the terminals of a definite group oii lines, and each relay of the other group adapted when energized to select some one unit in all of the relay groups of the first set, circuit connections from each individual relay of each group to the bank contacts of a step by step switch, a rack bearing a wiper adapted to pass over each set of bank contacts, a ratchet and operating mechanism therefor to move the rack and wiper step by step, means for holding the rack and wiper in position, and means for restoring the same to normal and i noperative position at will.

17. In a telephone exchange system, a plu- 'ality of line circuits, and a number oirelays less than the number of-line circuits divided into two sets, bearing a decimal relation to each other, each relay in the first set containing terminals of a definite group of ten lines, and other cooperating terminals to which the correspoinling pairs are mnlt-ipled in all the relays of the set, so as to form ten multiple stub circuits, each terminating in one only of the relays of the second set, cooperating contacts in the relays of the second set all connected in parallel, and a step by step switch for each set of relays, having ten bank contacts connected respectively to the windings on the relays in its set, a rack carrying a wiper, an electromagnetically controlled pawl :lor moving the ra'cl-r. step by step, a holding pawl for the rack, and releasing means therefor, whereby the actuation of the said switches a number of steps corresponding to the digits of the line nu1nher desired to be connected, will produce the energization of the relay in the group set containing a terminal. of the line wanted, and the relay in the individual set which will select the desired unit in the group.

In testimony whereot I altix my slgnature in presence of two witnesses.

EDlVARD E. CLEMENT.

ll'itncsses F. Enmons'ron, Jr., James H. lllAnn. 

